lemon/edge_set.h
changeset 2499 c97596611d59
parent 2391 14a343be7a5a
child 2553 bfced05fa852
equal deleted inserted replaced
22:a17ca6e73d6a 23:7432b968e792
   239   ///
   239   ///
   240   /// \param _Graph The type of the graph which shares its node set with 
   240   /// \param _Graph The type of the graph which shares its node set with 
   241   /// this class. Its interface must conform to the \ref concepts::Graph
   241   /// this class. Its interface must conform to the \ref concepts::Graph
   242   /// "Graph" concept.
   242   /// "Graph" concept.
   243   ///
   243   ///
   244   /// In the edge extension and removing it conforms to the 
       
   245   /// \ref concepts::Graph "Graph" concept.
       
   246   template <typename _Graph>
   244   template <typename _Graph>
   247   class ListEdgeSet : public EdgeSetExtender<ListEdgeSetBase<_Graph> > {
   245   class ListEdgeSet : public EdgeSetExtender<ListEdgeSetBase<_Graph> > {
   248 
   246 
   249   public:
   247   public:
   250 
   248 
   318       Parent::initalize(graph, nodes);
   316       Parent::initalize(graph, nodes);
   319     }
   317     }
   320     
   318     
   321   };
   319   };
   322 
   320 
       
   321   template <typename _Graph>
       
   322   class ListUEdgeSetBase {
       
   323   public:
       
   324 
       
   325     typedef _Graph Graph;
       
   326     typedef typename Graph::Node Node;
       
   327     typedef typename Graph::NodeIt NodeIt;
       
   328 
       
   329   protected:
       
   330 
       
   331     struct NodeT {
       
   332       int first_out;
       
   333       NodeT() : first_out(-1) {}
       
   334     };
       
   335 
       
   336     typedef DefaultMap<Graph, Node, NodeT> NodesImplBase;
       
   337 
       
   338     NodesImplBase* nodes;
       
   339 
       
   340     struct EdgeT {
       
   341       Node target;
       
   342       int prev_out, next_out;
       
   343       EdgeT() : prev_out(-1), next_out(-1) {}
       
   344     };
       
   345 
       
   346     std::vector<EdgeT> edges;
       
   347 
       
   348     int first_edge;
       
   349     int first_free_edge;
       
   350 
       
   351     const Graph* graph;
       
   352 
       
   353     void initalize(const Graph& _graph, NodesImplBase& _nodes) {
       
   354       graph = &_graph;
       
   355       nodes = &_nodes;
       
   356     }
       
   357     
       
   358   public:
       
   359 
       
   360     class UEdge {
       
   361       friend class ListUEdgeSetBase;
       
   362     protected:
       
   363 
       
   364       int id;
       
   365       explicit UEdge(int _id) { id = _id;}
       
   366 
       
   367     public:
       
   368       UEdge() {}
       
   369       UEdge (Invalid) { id = -1; }
       
   370       bool operator==(const UEdge& edge) const {return id == edge.id;}
       
   371       bool operator!=(const UEdge& edge) const {return id != edge.id;}
       
   372       bool operator<(const UEdge& edge) const {return id < edge.id;}
       
   373     };
       
   374 
       
   375     class Edge {
       
   376       friend class ListUEdgeSetBase;
       
   377     protected:
       
   378       Edge(int _id) : id(_id) {}
       
   379       int id;
       
   380     public:
       
   381       operator UEdge() const { return uEdgeFromId(id / 2); }
       
   382 
       
   383       Edge() {}
       
   384       Edge(Invalid) : id(-1) {}
       
   385       bool operator==(const Edge& edge) const { return id == edge.id; }
       
   386       bool operator!=(const Edge& edge) const { return id != edge.id; }
       
   387       bool operator<(const Edge& edge) const { return id < edge.id; }
       
   388     };
       
   389 
       
   390     ListUEdgeSetBase() : first_edge(-1), first_free_edge(-1) {} 
       
   391 
       
   392     UEdge addEdge(const Node& u, const Node& v) {
       
   393       int n;
       
   394 
       
   395       if (first_free_edge == -1) {
       
   396 	n = edges.size();
       
   397 	edges.push_back(EdgeT());
       
   398 	edges.push_back(EdgeT());
       
   399       } else {
       
   400 	n = first_free_edge;
       
   401 	first_free_edge = edges[n].next_out;
       
   402       }
       
   403       
       
   404       edges[n].target = u;
       
   405       edges[n | 1].target = v;
       
   406 
       
   407       edges[n].next_out = (*nodes)[v].first_out;
       
   408       if ((*nodes)[v].first_out != -1) {
       
   409 	edges[(*nodes)[v].first_out].prev_out = n;
       
   410       }
       
   411       (*nodes)[v].first_out = n;
       
   412       edges[n].prev_out = -1;
       
   413       
       
   414       if ((*nodes)[u].first_out != -1) {
       
   415 	edges[(*nodes)[u].first_out].prev_out = (n | 1);
       
   416       }
       
   417       edges[n | 1].next_out = (*nodes)[u].first_out;
       
   418       (*nodes)[u].first_out = (n | 1);
       
   419       edges[n | 1].prev_out = -1;
       
   420 
       
   421       return UEdge(n / 2);
       
   422     }
       
   423 
       
   424     void erase(const UEdge& edge) {
       
   425       int n = edge.id * 2;
       
   426       
       
   427       if (edges[n].next_out != -1) {
       
   428 	edges[edges[n].next_out].prev_out = edges[n].prev_out;
       
   429       } 
       
   430 
       
   431       if (edges[n].prev_out != -1) {
       
   432 	edges[edges[n].prev_out].next_out = edges[n].next_out;
       
   433       } else {
       
   434 	(*nodes)[edges[n | 1].target].first_out = edges[n].next_out;
       
   435       }
       
   436 
       
   437       if (edges[n | 1].next_out != -1) {
       
   438 	edges[edges[n | 1].next_out].prev_out = edges[n | 1].prev_out;
       
   439       } 
       
   440 
       
   441       if (edges[n | 1].prev_out != -1) {
       
   442 	edges[edges[n | 1].prev_out].next_out = edges[n | 1].next_out;
       
   443       } else {
       
   444 	(*nodes)[edges[n].target].first_out = edges[n | 1].next_out;
       
   445       }
       
   446       
       
   447       edges[n].next_out = first_free_edge;
       
   448       first_free_edge = n;      
       
   449            
       
   450     }
       
   451 
       
   452     void clear() {
       
   453       Node node;
       
   454       for (first(node); node != INVALID; next(node)) {
       
   455         (*nodes)[node].first_out = -1;
       
   456       }
       
   457       edges.clear();
       
   458       first_edge = -1;
       
   459       first_free_edge = -1;
       
   460     }
       
   461 
       
   462     void first(Node& node) const {
       
   463       graph->first(node);
       
   464     }
       
   465 
       
   466     void next(Node& node) const {
       
   467       graph->next(node);
       
   468     }
       
   469 
       
   470     void first(Edge& edge) const {
       
   471       Node node;
       
   472       first(node);
       
   473       while (node != INVALID && (*nodes)[node].first_out == -1) {
       
   474         next(node);
       
   475       }
       
   476       edge.id = (node == INVALID) ? -1 : (*nodes)[node].first_out;
       
   477     }
       
   478 
       
   479     void next(Edge& edge) const {
       
   480       if (edges[edge.id].next_out != -1) {
       
   481 	edge.id = edges[edge.id].next_out;
       
   482       } else {
       
   483 	Node node = edges[edge.id ^ 1].target;
       
   484 	next(node);
       
   485         while(node != INVALID && (*nodes)[node].first_out == -1) {
       
   486           next(node);
       
   487         }
       
   488 	edge.id = (node == INVALID) ? -1 : (*nodes)[node].first_out;
       
   489       }      
       
   490     }
       
   491 
       
   492     void first(UEdge& uedge) const {
       
   493       Node node;
       
   494       first(node);
       
   495       while (node != INVALID) {
       
   496         uedge.id = (*nodes)[node].first_out;
       
   497         while ((uedge.id & 1) != 1) {
       
   498           uedge.id = edges[uedge.id].next_out;
       
   499         }
       
   500         if (uedge.id != -1) {
       
   501           uedge.id /= 2;
       
   502           return;
       
   503         } 
       
   504         next(node);
       
   505       }
       
   506       uedge.id = -1;
       
   507     }
       
   508 
       
   509     void next(UEdge& uedge) const {
       
   510       Node node = edges[uedge.id * 2].target;
       
   511       uedge.id = edges[(uedge.id * 2) | 1].next_out;
       
   512       while ((uedge.id & 1) != 1) {
       
   513         uedge.id = edges[uedge.id].next_out;
       
   514       }
       
   515       if (uedge.id != -1) {
       
   516         uedge.id /= 2;
       
   517         return;
       
   518       } 
       
   519       next(node);
       
   520       while (node != INVALID) {
       
   521         uedge.id = (*nodes)[node].first_out;
       
   522         while ((uedge.id & 1) != 1) {
       
   523           uedge.id = edges[uedge.id].next_out;
       
   524         }
       
   525         if (uedge.id != -1) {
       
   526           uedge.id /= 2;
       
   527           return;
       
   528         } 
       
   529 	next(node);
       
   530       }
       
   531       uedge.id = -1;
       
   532     }
       
   533 
       
   534     void firstOut(Edge& edge, const Node& node) const {
       
   535       edge.id = (*nodes)[node].first_out;
       
   536     }
       
   537     
       
   538     void nextOut(Edge& edge) const {
       
   539       edge.id = edges[edge.id].next_out;        
       
   540     }
       
   541 
       
   542     void firstIn(Edge& edge, const Node& node) const {
       
   543       edge.id = (((*nodes)[node].first_out) ^ 1);
       
   544       if (edge.id == -2) edge.id = -1;
       
   545     }
       
   546 
       
   547     void nextIn(Edge& edge) const {
       
   548       edge.id = ((edges[edge.id ^ 1].next_out) ^ 1);
       
   549       if (edge.id == -2) edge.id = -1;
       
   550     }
       
   551 
       
   552     void firstInc(UEdge &edge, bool& dir, const Node& node) const {
       
   553       int de = (*nodes)[node].first_out;
       
   554       if (de != -1 ) {
       
   555         edge.id = de / 2;
       
   556         dir = ((de & 1) == 1);
       
   557       } else {
       
   558         edge.id = -1;
       
   559         dir = true;
       
   560       }
       
   561     }
       
   562     void nextInc(UEdge &edge, bool& dir) const {
       
   563       int de = (edges[(edge.id * 2) | (dir ? 1 : 0)].next_out);
       
   564       if (de != -1 ) {
       
   565         edge.id = de / 2;
       
   566         dir = ((de & 1) == 1);
       
   567       } else {
       
   568         edge.id = -1;
       
   569         dir = true;
       
   570       }
       
   571     }
       
   572 
       
   573     static bool direction(Edge edge) {
       
   574       return (edge.id & 1) == 1;
       
   575     }
       
   576 
       
   577     static Edge direct(UEdge uedge, bool dir) {
       
   578       return Edge(uedge.id * 2 + (dir ? 1 : 0));
       
   579     }
       
   580 
       
   581     int id(const Node& node) const { return graph->id(node); }
       
   582     static int id(Edge e) { return e.id; }
       
   583     static int id(UEdge e) { return e.id; }
       
   584 
       
   585     Node nodeFromId(int id) const { return graph->nodeFromId(id); }
       
   586     static Edge edgeFromId(int id) { return Edge(id);}
       
   587     static UEdge uEdgeFromId(int id) { return UEdge(id);}
       
   588 
       
   589     int maxNodeId() const { return graph->maxNodeId(); };
       
   590     int maxUEdgeId() const { return edges.size() / 2 - 1; }
       
   591     int maxEdgeId() const { return edges.size()-1; }
       
   592 
       
   593     Node source(Edge e) const { return edges[e.id ^ 1].target; }
       
   594     Node target(Edge e) const { return edges[e.id].target; }
       
   595 
       
   596     Node source(UEdge e) const { return edges[2 * e.id].target; }
       
   597     Node target(UEdge e) const { return edges[2 * e.id + 1].target; }
       
   598 
       
   599     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
       
   600 
       
   601     NodeNotifier& notifier(Node) const {
       
   602       return graph->notifier(Node());
       
   603     } 
       
   604 
       
   605     template <typename _Value>
       
   606     class NodeMap : public Graph::template NodeMap<_Value> {
       
   607     public:
       
   608 
       
   609       typedef typename _Graph::template NodeMap<_Value> Parent;
       
   610 
       
   611       explicit NodeMap(const ListUEdgeSetBase<Graph>& edgeset) 
       
   612 	: Parent(*edgeset.graph) {}
       
   613 
       
   614       NodeMap(const ListUEdgeSetBase<Graph>& edgeset, const _Value& value)
       
   615 	: Parent(*edgeset.graph, value) {}
       
   616 
       
   617       NodeMap& operator=(const NodeMap& cmap) {
       
   618         return operator=<NodeMap>(cmap);
       
   619       }
       
   620 
       
   621       template <typename CMap>
       
   622       NodeMap& operator=(const CMap& cmap) {
       
   623         Parent::operator=(cmap);
       
   624         return *this;
       
   625       }
       
   626     };
       
   627 
       
   628   };
       
   629 
   323   /// \ingroup semi_adaptors
   630   /// \ingroup semi_adaptors
   324   ///
   631   ///
   325   /// \brief Graph using a node set of another graph and an
   632   /// \brief Graph using a node set of another graph and an
   326   /// own uedge set.
   633   /// own uedge set.
   327   ///
   634   ///
   334   /// "Graph" concept.
   641   /// "Graph" concept.
   335   ///
   642   ///
   336   /// In the edge extension and removing it conforms to the 
   643   /// In the edge extension and removing it conforms to the 
   337   /// \ref concepts::UGraph "UGraph" concept.
   644   /// \ref concepts::UGraph "UGraph" concept.
   338   template <typename _Graph>
   645   template <typename _Graph>
   339   class ListUEdgeSet 
   646   class ListUEdgeSet : public UEdgeSetExtender<ListUEdgeSetBase<_Graph> > {
   340     : public UEdgeSetExtender<UndirGraphExtender<ListEdgeSetBase<_Graph> > > {
   647 
   341 
   648   public:
   342   public:
   649 
   343 
   650     typedef UEdgeSetExtender<ListUEdgeSetBase<_Graph> > Parent;
   344     typedef UEdgeSetExtender<UndirGraphExtender<
       
   345       ListEdgeSetBase<_Graph> > > Parent;
       
   346     
   651     
   347     typedef typename Parent::Node Node;
   652     typedef typename Parent::Node Node;
   348     typedef typename Parent::Edge Edge;
   653     typedef typename Parent::Edge Edge;
   349     
   654     
   350     typedef _Graph Graph;
   655     typedef _Graph Graph;
   659       return nodes.attached();
   964       return nodes.attached();
   660     }
   965     }
   661     
   966     
   662   };
   967   };
   663 
   968 
       
   969 
       
   970   template <typename _Graph>
       
   971   class SmartUEdgeSetBase {
       
   972   public:
       
   973 
       
   974     typedef _Graph Graph;
       
   975     typedef typename Graph::Node Node;
       
   976     typedef typename Graph::NodeIt NodeIt;
       
   977 
       
   978   protected:
       
   979 
       
   980     struct NodeT {
       
   981       int first_out;
       
   982       NodeT() : first_out(-1) {}
       
   983     };
       
   984 
       
   985     typedef DefaultMap<Graph, Node, NodeT> NodesImplBase;
       
   986 
       
   987     NodesImplBase* nodes;
       
   988 
       
   989     struct EdgeT {
       
   990       Node target;
       
   991       int next_out;
       
   992       EdgeT() {}
       
   993     };
       
   994 
       
   995     std::vector<EdgeT> edges;
       
   996 
       
   997     const Graph* graph;
       
   998 
       
   999     void initalize(const Graph& _graph, NodesImplBase& _nodes) {
       
  1000       graph = &_graph;
       
  1001       nodes = &_nodes;
       
  1002     }
       
  1003     
       
  1004   public:
       
  1005 
       
  1006     class UEdge {
       
  1007       friend class SmartUEdgeSetBase;
       
  1008     protected:
       
  1009 
       
  1010       int id;
       
  1011       explicit UEdge(int _id) { id = _id;}
       
  1012 
       
  1013     public:
       
  1014       UEdge() {}
       
  1015       UEdge (Invalid) { id = -1; }
       
  1016       bool operator==(const UEdge& edge) const {return id == edge.id;}
       
  1017       bool operator!=(const UEdge& edge) const {return id != edge.id;}
       
  1018       bool operator<(const UEdge& edge) const {return id < edge.id;}
       
  1019     };
       
  1020 
       
  1021     class Edge {
       
  1022       friend class SmartUEdgeSetBase;
       
  1023     protected:
       
  1024       Edge(int _id) : id(_id) {}
       
  1025       int id;
       
  1026     public:
       
  1027       operator UEdge() const { return uEdgeFromId(id / 2); }
       
  1028 
       
  1029       Edge() {}
       
  1030       Edge(Invalid) : id(-1) {}
       
  1031       bool operator==(const Edge& edge) const { return id == edge.id; }
       
  1032       bool operator!=(const Edge& edge) const { return id != edge.id; }
       
  1033       bool operator<(const Edge& edge) const { return id < edge.id; }
       
  1034     };
       
  1035 
       
  1036     SmartUEdgeSetBase() {} 
       
  1037 
       
  1038     UEdge addEdge(const Node& u, const Node& v) {
       
  1039       int n = edges.size();
       
  1040       edges.push_back(EdgeT());
       
  1041       edges.push_back(EdgeT());
       
  1042       
       
  1043       edges[n].target = u;
       
  1044       edges[n | 1].target = v;
       
  1045 
       
  1046       edges[n].next_out = (*nodes)[v].first_out;
       
  1047       (*nodes)[v].first_out = n;
       
  1048 
       
  1049       edges[n | 1].next_out = (*nodes)[u].first_out;	
       
  1050       (*nodes)[u].first_out = (n | 1);
       
  1051 
       
  1052       return UEdge(n / 2);
       
  1053     }
       
  1054 
       
  1055     void clear() {
       
  1056       Node node;
       
  1057       for (first(node); node != INVALID; next(node)) {
       
  1058         (*nodes)[node].first_out = -1;
       
  1059       }
       
  1060       edges.clear();
       
  1061     }
       
  1062 
       
  1063     void first(Node& node) const {
       
  1064       graph->first(node);
       
  1065     }
       
  1066 
       
  1067     void next(Node& node) const {
       
  1068       graph->next(node);
       
  1069     }
       
  1070 
       
  1071     void first(Edge& edge) const { 
       
  1072       edge.id = edges.size() - 1;
       
  1073     }
       
  1074 
       
  1075     void next(Edge& edge) const {
       
  1076       --edge.id;
       
  1077     }
       
  1078 
       
  1079     void first(UEdge& edge) const { 
       
  1080       edge.id = edges.size() / 2 - 1;
       
  1081     }
       
  1082 
       
  1083     void next(UEdge& edge) const {
       
  1084       --edge.id;
       
  1085     }
       
  1086 
       
  1087     void firstOut(Edge& edge, const Node& node) const {
       
  1088       edge.id = (*nodes)[node].first_out;    
       
  1089     }
       
  1090     
       
  1091     void nextOut(Edge& edge) const {
       
  1092       edge.id = edges[edge.id].next_out;        
       
  1093     }
       
  1094 
       
  1095     void firstIn(Edge& edge, const Node& node) const {
       
  1096       edge.id = (((*nodes)[node].first_out) ^ 1);
       
  1097       if (edge.id == -2) edge.id = -1;
       
  1098     }
       
  1099 
       
  1100     void nextIn(Edge& edge) const {
       
  1101       edge.id = ((edges[edge.id ^ 1].next_out) ^ 1);
       
  1102       if (edge.id == -2) edge.id = -1;
       
  1103     }
       
  1104 
       
  1105     void firstInc(UEdge &edge, bool& dir, const Node& node) const {
       
  1106       int de = (*nodes)[node].first_out;
       
  1107       if (de != -1 ) {
       
  1108         edge.id = de / 2;
       
  1109         dir = ((de & 1) == 1);
       
  1110       } else {
       
  1111         edge.id = -1;
       
  1112         dir = true;
       
  1113       }
       
  1114     }
       
  1115     void nextInc(UEdge &edge, bool& dir) const {
       
  1116       int de = (edges[(edge.id * 2) | (dir ? 1 : 0)].next_out);
       
  1117       if (de != -1 ) {
       
  1118         edge.id = de / 2;
       
  1119         dir = ((de & 1) == 1);
       
  1120       } else {
       
  1121         edge.id = -1;
       
  1122         dir = true;
       
  1123       }
       
  1124     }
       
  1125 
       
  1126     static bool direction(Edge edge) {
       
  1127       return (edge.id & 1) == 1;
       
  1128     }
       
  1129 
       
  1130     static Edge direct(UEdge uedge, bool dir) {
       
  1131       return Edge(uedge.id * 2 + (dir ? 1 : 0));
       
  1132     }
       
  1133 
       
  1134     int id(Node node) const { return graph->id(node); }
       
  1135     static int id(Edge edge) { return edge.id; }
       
  1136     static int id(UEdge edge) { return edge.id; }
       
  1137 
       
  1138     Node nodeFromId(int id) const { return graph->nodeFromId(id); }
       
  1139     static Edge edgeFromId(int id) { return Edge(id); }
       
  1140     static UEdge uEdgeFromId(int id) { return UEdge(id);}
       
  1141 
       
  1142     int maxNodeId() const { return graph->maxNodeId(); };
       
  1143     int maxEdgeId() const { return edges.size() - 1; }
       
  1144     int maxUEdgeId() const { return edges.size() / 2 - 1; }
       
  1145 
       
  1146     Node source(Edge e) const { return edges[e.id ^ 1].target; }
       
  1147     Node target(Edge e) const { return edges[e.id].target; }
       
  1148 
       
  1149     Node source(UEdge e) const { return edges[2 * e.id].target; }
       
  1150     Node target(UEdge e) const { return edges[2 * e.id + 1].target; }
       
  1151 
       
  1152     typedef typename ItemSetTraits<Graph, Node>::ItemNotifier NodeNotifier;
       
  1153 
       
  1154     NodeNotifier& notifier(Node) const {
       
  1155       return graph->notifier(Node());
       
  1156     } 
       
  1157 
       
  1158     template <typename _Value>
       
  1159     class NodeMap : public Graph::template NodeMap<_Value> {
       
  1160     public:
       
  1161 
       
  1162       typedef typename _Graph::template NodeMap<_Value> Parent;
       
  1163 
       
  1164       explicit NodeMap(const SmartUEdgeSetBase<Graph>& edgeset) 
       
  1165 	: Parent(*edgeset.graph) { }
       
  1166 
       
  1167       NodeMap(const SmartUEdgeSetBase<Graph>& edgeset, const _Value& value)
       
  1168 	: Parent(*edgeset.graph, value) { }
       
  1169 
       
  1170       NodeMap& operator=(const NodeMap& cmap) {
       
  1171         return operator=<NodeMap>(cmap);
       
  1172       }
       
  1173 
       
  1174       template <typename CMap>
       
  1175       NodeMap& operator=(const CMap& cmap) {
       
  1176         Parent::operator=(cmap);
       
  1177         return *this;
       
  1178       }
       
  1179     };
       
  1180 
       
  1181   };
       
  1182 
   664   /// \ingroup semi_adaptors
  1183   /// \ingroup semi_adaptors
   665   ///
  1184   ///
   666   /// \brief Graph using a node set of another graph and an
  1185   /// \brief Graph using a node set of another graph and an
   667   /// own uedge set.
  1186   /// own uedge set.
   668   ///
  1187   ///
   675   /// "Graph" concept.
  1194   /// "Graph" concept.
   676   ///
  1195   ///
   677   /// In the edge extension and removing it conforms to the 
  1196   /// In the edge extension and removing it conforms to the 
   678   /// \ref concepts::UGraph "UGraph" concept.
  1197   /// \ref concepts::UGraph "UGraph" concept.
   679   template <typename _Graph>
  1198   template <typename _Graph>
   680   class SmartUEdgeSet 
  1199   class SmartUEdgeSet : public UEdgeSetExtender<SmartUEdgeSetBase<_Graph> > {
   681     : public UEdgeSetExtender<UndirGraphExtender<SmartEdgeSetBase<_Graph> > > {
  1200 
   682 
  1201   public:
   683   public:
  1202 
   684 
  1203     typedef UEdgeSetExtender<SmartUEdgeSetBase<_Graph> > Parent;
   685     typedef UEdgeSetExtender<UndirGraphExtender<
       
   686       SmartEdgeSetBase<_Graph> > > Parent;
       
   687     
  1204     
   688     typedef typename Parent::Node Node;
  1205     typedef typename Parent::Node Node;
   689     typedef typename Parent::Edge Edge;
  1206     typedef typename Parent::Edge Edge;
   690     
  1207     
   691     typedef _Graph Graph;
  1208     typedef _Graph Graph;